1. Field of the Invention
The present invention relates to a method for manufacturing a liquid discharge head for discharging liquid, and specifically, to a method for manufacturing an ink jet recording head for recording on a recording medium by discharging ink thereon.
2. Description of the Related Art
For example, liquid discharge heads for discharging liquid are applied to the ink jet recording method in which ink is discharged onto a recording medium for recording thereon. In general, the ink jet recording head includes a flow path, a discharge energy generating element provided in a part of the flow path, and a fine discharge port for discharging ink by energy generated in the element.
A method for manufacturing a liquid discharge head applicable to the ink jet recording head described above by photolithography as employed in the semiconductor manufacturing technology is disclosed in Japanese Patent Application Laid-Open No. 2006-82329. According to this method, a member is formed on one silicon wafer, the member including an element for generating energy to be used for discharging liquid, a discharge port associated therewith, and a flow path. After that, the silicon wafer is separated into a plurality of chip units by dicing, thereby providing discrete recording heads.
On the other hand, a method for marking history information on each of the chip units on the wafer before being diced is disclosed in Japanese Patent Application Laid-Open No. H05-74748. According to this method, a polysilicon fuse element region dedicated to storing history information is provided within the semiconductor chip, and then damaged by a marking laser device, thereby marking the history information. As marked contents, the information on the position of the chips within the wafer, the lot number of the wafer, the wafer serial number, and the like are disclosed.
However, in manufacturing the ink jet recording head, when considering the recording and using the history information during manufacturing, concerns as described below are raised about employing the method disclosed in Japanese Patent Application Laid-Open No. H05-74748.
During the use of the ink jet recording head, it is expected that the surface of the head of chip unit may have ink with some polarity adhered thereto or may contact with recording sheets. To ensure that the history information is maintained for a long time while the chip experiences such events, it is required for the history information recording pattern to have reliability related characteristics such as solvent resistance, abrasion resistance, and the like. Further, it is conceivable to provide an additional member for protecting the history information recording pattern. However, it is difficult to select the material of the protective member by taking into account the recognizability of the history information pattern, more specifically, the effects of the material on legibility such as viewability and the like, the property of intimate contact between the history information pattern and the protective member, and the reliability of the protective member.